Antibiotics and performance

"Tom Ace" wrote in message
oups.com...
Mike Owens wrote:

"L" isomers only refer to amino acids.

I'd thought that the name Levaquin referred to it
being the levorotatory isomer, and a Google search
for L-isomer Levaquin will return tons o' pages.
Are all those pages using the term inappropriately?


Tom Ace

Either the "pages" are using the term inappropriately or you are. The
"levo" in levorotary should only use a lower case "l" (lower case d for
dextrorotary). Upper case L or D refer to a separate nomenclature used for
amino acids. It might seem like nitpicking, but no reason not to get it
correct.
-Mike

Tom Ace wrote:
Peter Cole wrote:


[...] Both
times I was on 2 drugs simultaneously, Flagyl and Levaquin, both are
relatively new synthetics, [...]


Flagyl (metronidazole) has been around for over 30 years.

Levaquin (levofloxacin) is sort of new. It's the L-isomer
of Floxin (ofloxacin), which had been patented in 1983.

http://www.vh.org/adult/provider/pharmacyservices/PTNews/2002/08PTNews.html

"The development of the fluoroquinolone class of antibiotics began in
the 1960s. Fluorination of the quinolones led to the development of the
first second-generation agent, norfloxacin, released in 1986.
Ciprofloxacin, a second-generation fluoroquinolone released in 1987,
became the first widely utilized systemic quinolone. Modifications to
improve dosing frequency, increase bioavailability, and widen
fluoroquinolone spectrum of activity resulted in the evolution of the
third generation fluoroquinolones. The third generation agents
(levofloxacin, moxifloxacin, sparfloxacin, grepafloxacin, and
gatifloxacin) were introduced in the late 1990s"

I guess Flagyl has been around since the 60's, and apparently is a
synthetic version of an extracted natural antibiotic.

I guess the point I was trying to make is that antibiotic agents work by
very different mechanisms, so the side effects may be very different.
Perhaps all antibiotics don't hamper performance, just some, and likely
that varies between individuals.

Fluoroquinolone variants have been developed, and many have been
rejected for toxicity. Current research continues on this class of
compounds in anti-tumor applications. Some "antibiotics" seem to blur
the line between the traditional definition and that of chemotherapy.

Tom Ace wrote:
Peter Cole wrote:


[...] Both
times I was on 2 drugs simultaneously, Flagyl and Levaquin, both are
relatively new synthetics, [...]


Flagyl (metronidazole) has been around for over 30 years.

Levaquin (levofloxacin) is sort of new. It's the L-isomer
of Floxin (ofloxacin), which had been patented in 1983.

Here's a blurb from
http://www.eff.org/Misc/Publications/Bruce_Sterling/FSF_columns/fsf.15
which roughly describes categorical differences in common antibiotic
families:

"Beta-lactam can not only mimic, subvert and destroy the assembly
enzymes, but it can even eat away peptide-chain mortar already in place.
And since mammalian cells never use any peptidoglycans, they are never
ruptured by penicillin (although penicillin does sometimes provoke
serious allergic reactions in certain susceptible patients). "

"Today there are more than fifty different penicillins and
seventy-five cephalosporins, all of which use beta-lactam rings in one
form or another."

"Antibiotics were discovered that could break-up or jam-up a cell's
protein synthesis; drugs such as tetracycline, streptomycin, gentamicin,
and chloramphenicol. These drugs creep through the porins deep inside
the cytoplasm and lock onto the various vulnerable sites in the RNA
protein factories. This RNA sabotage brings the cell's basic
metabolism to a seething halt, and the bacterium chokes and dies."

"The final major method of antibiotic attack was an assault on
bacterial DNA. These compounds, such as the sulphonamides, the
quinolones, and the diaminopyrimidines, would gum up bacterial DNA
itself, or break its strands, or destroy the template mechanism that
reads from the DNA and helps to replicate it. Or, they could ruin the
DNA's nucleotide raw materials before those nucleotides could be plugged
into the genetic code. Attacking bacterial DNA itself was the most
sophisticated attack yet on bacteria, but unfortunately these DNA
attackers often tended to be toxic to mammalian cells as well."

Both Levaquin and Flagyl are in the third category. Other than allergic
reactions and whole-body flora considerations, I think antibiotics in
the first 2 categories may have more benign (and predictable) side effects.

On Fri, 11 Nov 2005 16:24:59 +0100, Derk wrote:

yeah, and it's a realy shame. Should be forbidden immediately. We'll all end
up with bacterial infections that can't be controlled by antibiotics any
more. Luckily, I saw a documentary on Phage treatment in Georgia (not the
US!) where viruses are used to kill bacteria.

I believe a news item a few weeks ago said that phage-resistant bacteria
had been spotted in the lab. It's not a panacea.

Incidentally, that Georgia/Phage thing featured *heavily* in the book
_Darwin's Radio_ by hard-SF great Greg Bear (dammit, I wanted to type
Brin, I'm glad I doublechecked -- The Killer B's, Bear, Brin, and Benford
are names I confuse easily).

Jasper